Tensioning device

ABSTRACT

A tensioning device for use with sway braces which may be used to interconnect vertical shelving supports wherein the tensioning device in the form of a circular plate to which a plurality of the sway braces are secured is rotated to place a tensioning force on the sway braces and then secured to maintain the tensioning force.

United States Patent [191 Jarvis l l TENSIONING DEVICE [75] Inventor:Edward M. Jarvis, Ambler, Pa. [73] Assignee: Standard Pressed Steel Co.,

[58] Field of Search 248/351; 52/638, 645, 223, 52/224; 287/535, 58 R[56] References Cited UNITED STATES PATENTS 311,165 l/l885 Adams 52/6381,193,767 8/1916 Crisell 52/82 July 16, 1974 1,677,738 7/1928 Sumpter etal. 52/638 2,067,709 l/l937 Humphrey 52/655 X 2,506,824 5/1950 Brownetal. ..'24'8/29l X Primary Examiner-J. Franklin Foss Attorney, Agent,or Firm-Andrew L. Ney; Robert P.

Seitter [57 ABSTRACT 9 Claims, 4 Drawing Figures PATENTED JUL 1 61974mean The present invention relates to tensioning devices and more inparticular to a' tensioning device for use with sway braces of the typeto brace vertical supports useful in providing open shelving units.

Typically open shelving units comprise a plurality of spaced verticalsupport units to which are secured horizontal shelving members atdesired spacings. The vertical support members are interconnected bycrossed sway braces to impart rigidity to the free standing shelvingunit and prevent-the shelving unit from collapsing. Where wide spanshelves are used the sway braces are long and, hence, flimsy and do notprovide a rigid and secure sway brace.

It is therefore an object of the present invention to provide atensioning device for use with sway braces to provide a readilyassembled sway brace system of rigid and secure construction.

It is a further object of the present invention to provide a tensioningdevice which utilizes shorter sway braces than in conventional systemsthereby providing a stiffer and more stable tensioning system. I

A further object of the present invention is to provide a tensioningdevice in the form of a disc to which a plurality of sway braces areloosely attached and which is readily tensioned by merely rotating thedisc to impart a tension to the interconnected sway brace members andwhich is readily secured by a single bolt connection. I

These and other objects of the presentinvention will be more readilyapparent after a consideration of the following specification inconjunction with the accompanying drawings.

In the drawings:

FIG. 1 is an elevational view of a section of open shelving showing thetensioning device of the present invention interconnecting a pair ofvertical support members;

FIG. 2 is an elevational view on an enlarged scale of the tensioningdevice of the present invention at an initial stage of installation;

FIG. 3 is a view similar to .FIG. 2 showing the tensioning device in asecured position after tension. has been applied; and

FIG. 4 is a partial sectional view taken along the line 4-4 of FIG. 3.

With reference to the drawings and particularly FIGS. 1 and. 2, atypical section of open shelving is shown wherein a pair of verticalsupport posts 12 and 14 are interconnected by sway braces.

The vertical posts 12 and 14 are used to support horizontal shelvingmembers (not shown) and are provided with bracket members 16, 18, and22, respectively, which are secured to the vertical posts 12 and14.'According to a preferred embodiment of the present invention fourrelatively short sway braces 24, 26, 28 and are provided. One end ofeach of the sway braces 24-30 is secured, respectively, to the brackets16-22 by a nut and bolt assembly 32. The other end of each 2. with eachof the nut and bolt assemblies being tightened only to the point ofproviding a light clamp fit. Sway brace 30 is also provided with anadditional bolt receiving hole 42 therein close to the end with the boltreceiving hole 34.

In assembling the tensioning device of the present invention the swaybraces 24-30 are positioned with one of the sway braces 24-30 isprovided with a bolt receiving hole 34. A tensioning member which ispreferably in the form of a disc-like plate member 36 is provided with aplurality of bolt receiving apertures 38 therethrough atcircumferentially spaced locations.

Each of the sway braces 24-30 is loosely secured to the tensioning disc36 by nut and bolt assemblies 40 end secured to the vertical postmembers and the other end secured to the tensioning disc 36 by therespective nut and bolt assemblies 32 and 40. These nut and boltassemblies are tightened to provide-a light clamp load so that-the swaybraces can be pivoted relative to the support brackets and thetensioning disc.

After this initial assembly step, the tensioning disc 36 is rotated,-asindicated by the direction of the arrow in FIG. 3, to an angularlyoffset position and this rotation of the tensioning disc 36 causes eachof the sway braces to pivot about thenut and bolt assemblies 32 and 40.Because disc 36 is rotated thelinear distance between the respective nutand bolt assemblies is lengthened to create a tension load on the swaybraces. At this juncture the position of the through hole 42 in swaybrace 30 relative to the tensioning disc 36 is located and a throughhole 44 is drilledthrough the tensioning disc 36 at the indicatedposition.

With the tensioning disc maintained in its tension excured by a nutmember 48. Bolt 46 now positions the tensioning disc 36 in its fixedrelationship and nut 48 may be tightened as well as the nut and boltassemblies 32 and 40 to firmly position and secure the sway braces andthe tensioning disc 36.

Alternatively, tensioning disc 36 can be provided with a lost motionslot in arcuate registry with through hole 42 in sway brace 30 so thatonce the proper position for tensioning disc 36 is achieved the securingbolt 46 can be readily inserted and secured by nut48.

The present invention provides a relatively simple and extremelyflexible device for tensioning sway braces between vertically extendingpost members and provides'the significant advantage that high tensionloads may be imparted to the sway braces depending upon the degree ofrotation to which the tensioning disc is subjected. Because thetensioning discis located midway along the connecting span for aconventional sway brace, the sway braces used with the present inventionare approximately half as long as conventional sway braces and theshortened sway braces provide a stiffer bracing member between adjacentvertical posts.

What is claimed is: 1. A tensioning device to tension brace membersextending between at least a'pair of spaced vertical sup- 3. Atensioning device as defined in claim 1 wherein at least two bracemembers extend from each said vertical post to said plate memberand'said brace members are secured to said vertical posts at verticallyspaced positions. r

4. The tensioning device, as defined in claim 3 wherein said bracemembers are secured to said plate memberat circumferentially spacedlocations on said plate member whereby rotation of said plate memberfrom said first position to said second position effects an increase inthe linear distance between the securing points of each brace memberthereby to impart said tensioning force.

5. The tensioning device as defined in claim 1 wherein said meanscooperable between said one brace member and said plate member to retainsaid tensioning member in said second position comprises aboltengageable through aligned holes in said one brace member and said platemember.

6. The tensioning device as defined in claim 5 wherein said hole in saidplate member is a lost motion slot.

7. A method fortensioning bracemembers between a pair of verticallydisposed support posts comprising,

securing one end of at least a pair of brace member to each saidvertical posts at vertically displaced positions,

pivotally securing the other end of each said brace member to a platemember with each said brace member being secured to said plate member atcircumferentially spaced locations,

rotating said plate member to a position angularly offset from itsinitial position to effect a tensioning force in each said brace member,and

positively securing one of said brace members to said tensioning memberto fix said plate member in said angularlyoffset position and maintainthe tensioning force on said brace members.

8. The method as defined in claim 7 wherein said step of pivotallysecuring said brace members to said plate member comprises bolting saidbrace members to said plate member with a nut and bolt assembly andengaging said nut to provide a light clamp load.

9. The method as defined in claim 8 wherein said step of positivelysecuring said one brace member to said plate member comprises fasteningsaid one brace member to said plate member with a bolt passing throughaligned holes and engaging said boltwith a nut to effect a clampingload.

1. A tensioning device to tension brace members extending between atleast a pair of spaced vertical support posts comprising: a plurality ofbrace members each having one end secured to one of said verticalsupport posts, the other end of each said brace members being pivotallysecured to a plate member, said plate member being rotatable from afirst position wherein no tensioning force is imparted to said bracemembers to a second position angularly offset from said first positionto effectively impart a tensioning force to each of said brace members,and means cooperable between one of said brace members and said platemember to retain said plate member in said second position after it hasbeen rotated from said first position.
 2. A tensioning device as definedin claim 1 wherein said brace members are each pivotally secured to saidplate member by bolt and nut assemblies which are maintained to providea light clamping load until said plate member is rotated into saidsecond position.
 3. A tensioning device as defined in claim 1 wherein atleast two brace members extend from each said vertical post to saidplate member and said brace members are secured to said veRtical postsat vertically spaced positions.
 4. The tensioning device as defined inclaim 3 wherein said brace members are secured to said plate member atcircumferentially spaced locations on said plate member whereby rotationof said plate member from said first position to said second positioneffects an increase in the linear distance between the securing pointsof each brace member thereby to impart said tensioning force.
 5. Thetensioning device as defined in claim 1 wherein said means cooperablebetween said one brace member and said plate member to retain saidtensioning member in said second position comprises a bolt engageablethrough aligned holes in said one brace member and said plate member. 6.The tensioning device as defined in claim 5 wherein said hole in saidplate member is a lost motion slot.
 7. A method for tensioning bracemembers between a pair of vertically disposed support posts comprising,securing one end of at least a pair of brace member to each saidvertical posts at vertically displaced positions, pivotally securing theother end of each said brace member to a plate member with each saidbrace member being secured to said plate member at circumferentiallyspaced locations, rotating said plate member to a position angularlyoffset from its initial position to effect a tensioning force in eachsaid brace member, and positively securing one of said brace members tosaid tensioning member to fix said plate member in said angularly offsetposition and maintain the tensioning force on said brace members.
 8. Themethod as defined in claim 7 wherein said step of pivotally securingsaid brace members to said plate member comprises bolting said bracemembers to said plate member with a nut and bolt assembly and engagingsaid nut to provide a light clamp load.
 9. The method as defined inclaim 8 wherein said step of positively securing said one brace memberto said plate member comprises fastening said one brace member to saidplate member with a bolt passing through aligned holes and engaging saidbolt with a nut to effect a clamping load.